/*common*/
body{
    margin: 0;
    padding: 0;
    font-size: 1em;
    color: #fff;
    background: url("../images/banner.jpg") fixed no-repeat center;
    background-size: cover;/*IE7 IE8²»Ö§³Ö*/
}
h1{
    font-size: 2em;
}
h2{
    font-size: 1.75em;
}
h3{
    font-size: 1.5em;
}
ul{
    margin: 0;
    padding: 0;
    list-style: none;
}
p {
    font-size: 16px;
    letter-spacing: 1px;
}
.sub-heading {
    line-height: 1.875em;
    margin: 2em 0;
    font-size: 1.125em;
}
.hr{
    margin: 20px auto;
    width: 100%;
    height: 2px;
}
.wrapper {
    margin: 0 auto;
    max-width: 1080px;
}
.clearfloat:after{
    content: '';
    display: block;
    clear: both;
}
a {
    text-decoration: none;
    color: #fff;
}
/*header*/
/*nav*/
header {
    background: rgba(0,0,0,0.3);
}
nav {
    height: 3.125em;
    background: transparent;
    font-size: 1em;
}

.fixed {
    position: fixed;
    top: 0;
    left: 0;
    margin: 0 auto;
    width: 100%;
    z-index: 1000;
}
.nav-bg-change {
    transition: background 500ms;
    background: #2E3842;
}
nav .logo {
    float: left;
    margin-left: 1.25em;
    font-size: 1.25em;
    font-weight: 700;
    letter-spacing: 1px;
}
nav .menu-toggle {
    position: relative;
    float: right;
    margin-right: 1.25em;
    text-transform: uppercase;
    letter-spacing: 1px;
}

nav .menu-toggle a, nav .logo a{
    display: inline-block;
    height: inherit;
}
nav .menu-toggle a {
    line-height: 3.125em;
}
nav .logo a {
    line-height: 2.5em;
}
nav .menu-toggle .menu-bars {
    display: inline-block;
    margin-left: 0.3125em;
    background: url(../images/menu-bars.png) no-repeat center;
    background-size: cover;
    width: 0.875em;
    height: 0.875em;
}
#menu {
    display: none;
    position: absolute;
    top: 3.125em;
    right: -1.25em;
    background: rgba(0,0,0,0.4);
    filter: progid:DXImageTransform.Microsoft.gradient(startColorStr='#7A000000', EndColorStr='#7A0000000');/*IE8-*/
}
#menu ul {
    margin: 0 auto;
    padding: 0;
    list-style: none;
}
#menu ul li{
    margin:0 auto;
    padding: 0.625em 1.25em;
    text-align: center;
    letter-spacing: 1px;
    border-bottom: 0.0625em solid rgba(255,255,255,0.2);
}
#menu ul li:hover {
    background: rgba(255,255,255,0.2);
    filter: progid:DXImageTransform.Microsoft.gradient(startColorStr='#36FFFFFF', EndColorStr='#36FFFFFF');/*IE8-*/
}
#menu ul li a{
    display: inline-block;
    width: 6.25em;
    height: 2.5em;
    line-height: 2.5em;
}
/*banner*/
#banner {
    height: 600px;
    background: transparent;
}
#banner .inner{
    position: relative;
    top: 5em;
    margin: 0 auto;
    max-width: 18.75em;
    text-align: center;
}
#banner h1 {
    margin: 0;
    padding: 0.75em;
    border-top: 0.125em solid #fff;
    border-bottom: 0.125em solid #fff;
}
#know-more-btn {
    position: relative;
    top: 5em;
    margin: 0 auto;
    padding: 0.375em 0;
    display: block;
    width: 50%;
    background: #ed4933;
    outline: none;
    border: none;
    border-radius: 0.375em;
    text-align: center;
    font-size: 1.125em;
    letter-spacing: 2px;
    color: #fff;
}
#know-more-btn .arrow {
    margin: 0.375em auto 0 auto;
    display: block;
    content: '';
    height: 30px;
    width: 30px;
    background: url(../images/arrow.png) no-repeat center;
    background-size: contain;
}
/*content*/
/*green-section*/
.green-section {
    background: rgba(33,176,188,0.9);
    text-align: center;
    padding: 6.25em;
}
.green-section .hr{
    background: rgba(0,0,0,0.1);
    width: 60%;
}
.icon-group {
    margin-top: 3.75em;
}
.icon-group .icon {
    display: inline-block;
    width: 5em;
    height: 5em;
    margin: 0 1.875em;
    text-align: center;
    text-transform: uppercase;
    font-weight: 900;
}
.icon-group .icon.html{
    background: url("../images/html.png") no-repeat center bottom;
}
.icon-group .icon.css{
    background: url("../images/css.png") no-repeat center bottom;
}
.icon-group .icon.js{
    background: url("../images/js.png") no-repeat center bottom;
}
/*gray-section*/
.gray-section {
    background: rgba(0,0,0,0.9);
}
.article-preview:nth-child(odd){
    background: rgba(255,255,255,0.1);
}
.article-preview{
    padding: 1.25em;
}
.article-preview > div{
    float: left;
}
.img-section{
    width: 40%;
}
.img-section img{
    width:100%;
}
.text-section {
    width: 60%;
    padding-left: 1.25em;
    -webkit-box-sizing: border-box;
    -moz-box-sizing: border-box;
    box-sizing: border-box;
}
.text-section .sub-heading {
    margin: 1.25em 0;
}
/*purple-section*/
.purple-section {
    background: rgba(94, 64, 147, 0.9);
    padding: 6.25em 0;
}
.purple-section .heading-wrapper {
    margin: 0 auto;
    text-align: center;
}
.purple-section .heading-wrapper h2 {
    margin-top: 0;
}
.purple-section .hr {
    background: rgba(255,255,255,0.1);
    width: 60%;
}
.card {
    float: left;
    width: 50%;
    min-height: 18.75em;
    padding: 2.5em;
    -webkit-box-sizing: border-box;
    -moz-box-sizing: border-box;
    box-sizing: border-box;
}
.card:first-child {
    background: rgba(0,0,0,0.12);
}
.card:nth-child(2) {
    background: rgba(0,0,0,0.18);
}
/*footer*/
footer {
    background: #333;
    text-align: center;
    padding: 2.5em;
}
footer .share-group li{
    display: inline-block;
    padding: 0.6em;
}
footer .copy {
    margin-top: 1.25em;
}